Washing arrangement for fibrous materials



y 13, 1954 G. KULVlK ET AL 2,683,366

WASHING ARRANGEMENT FOR FIBROUS MATERIALS Filed Feb 23. 1950 HEQZ.

5r KIM' W W (wot.

BY Q 4 washing tanks or containers with screenybottoms.

Patented July 13, 1954 umreo PA-TENT OFFICE WASHING .ARBANGEMENI r0.EIBROUS Ma'rERn s Gun-nan Kulvikand' Lasse Johan Hannunkari, :Oulu,Finland Apm c imr ebruary 2.3., 19.50, "sem narians uGlaimsipriority,application Finland :Febnuary 26,111549 ,6 gGlaims.

The present invention relates toE an arrangement for washing fibrousmaterial; such;,as;pu lp.

In washing fibrous -materia1s;,-s uch as-che'mical pulp it hasheretofore been customary touse During the washing processwashing-liquid is ;delivered to thetank through the-t9 thereof anddisplaces, while flowing 1 downwards, the heavier ,liquor which isWithdrawnfrom theabottom of the tank through the-screen bottom.JI'anksof the kind described hava however thedisadvan- Secondly theV-liquid :ilow l. causes :a

thesize of passages throughthe material.

Objects of the invention are-the provision of-a washing tank in whichthe abovedescribed gdlS- advantages are overcome; provision of; ;an,appa.ratus in which the washing .process'is mapidly carried out so thatthe-number-of washing tanks necessary to produceva continuous washingprocess can be appreciably reduced; :r provision qfzan apparatus inwhichthe material to :be treated can be evenly and thoroughlyiawashed;provision tankaccording to a preferred embodiment of the ofa washingtank in which the chiefly downwardly directed pressure. in :the treatedmaterial "due to its own weight ispreventedifrom fQrming a compact layerof materials-hindering 1iquid Withthese objects in view-the -.present;invention mainly consists inan ,arrangementtforrwash- --ing fibrousmaterial and comprises-gin; combination, a substantially verticallyarranged tank having a wall formed. withan inletior material to bewashed at the upper end 0f; said tanksand an outlet for washed materialat the lower end' of the tank; at least one screeningqchamberdeviceincluding at least one inclin'ed' ;supp0rtingwp1ate member secured tothe inner surface ottherwall v -and pr j n from the .same' -downWard1y--into the interior of the tank, the inclinedesupporting 11312138 memberhaving the highest poinbthereef located adjacent to r the wall .of thegtank, ;the platemember being adapted -to 'support material :to-bewashed, inclined screen rneansee etending' :between the underside of the-suppQrti :plate membelwand th inner.surfaceofsth .wall was to iorm a.screening-chamberbounded; by: th -;:{sup- ,porting plate:memben-Ltherinner:surface;ofcthesgn in fltank and. controlled-h yavalve 3.

'2 wall, and therscreen :means, the screen means having -.at;least oneouter face outside the cham- --berand at least onerinner faceinside thechamber, theou ter faceof the inclined screen member 5facing-downwardly; ,and outlet means for a washing liquid located on thetank communicating ,with the vscreening phamber.

According to one embodiment of the present invention annular downwardlyinclined supportingplates project,trom' the inner surface of the tankinto the interior of the same and form to- -gether with downwardlyinclined annular screen m-embersa plurality of .annularscreeningchamberdevices-whichare provided with. outlet means for-a washingliquid.

,According to another: embodiment of the presl-ent- -invention-aplurality of radially extending .:,screening chamberdevices arelocated on the bot- -tomavallofthe ,tanlg-each of the screening chamwberdevices: having on top a downwardly inclined I supporting plate andincluding two lateral downvardlyinclinedscreen members, the plate andthe screenmembers forming radially extending "screening chamberscorninunicating with outlet 2 ,means for thewashing liquid.

-;'I;he ;inventionwil1 be best understood from the followingdescriptions of specific embodiments :when read-in connectionwiththe-accompanying drawingsinwhich:

Figrl isa verticalsectionalview of a washing p1 e sent invention;

Fig. 2 is a fragmentary vertical sectional View of another-embodimentofthe present invention;

and V .3 :is arbottom view of the arrangement whownin Fig; 1.

,iReferringnow-to Figs. 1 and 3, in an vupright washing tank i an inletla'for fibrous material .to be washed is located in the upper part ofthe tank, -and ;an outlet 2 for the washed material is -.arranged-inthe-center of the bottom lb of the Washing wateris --supplied throughthe water inlet lc.

.l-A -tpllllsality of ,annularscreening chamber devices;, A,-.-B, 3C areprovided, each screening cham l ber device including a downwardlyinclined anr ,nular-supporting plate member 5 having-the shape oftizuncatedcones whose highest point is'located adjacent to theivall ofthe tank. A screen means, 5 113 1118157 --the inclined annular screeninember .4 ex- ,z tends i-betweenttheunderside of the: supporting platemeinberg-iand the inner surface gQf the tank so-as'orm-asoreeningchamber. -.-Each screenamb s communi at w t nu c m an -.4

I, 8, respectively, which end in annular pipes 6a, la, and 8a,respectively, communicating with outlet pipes 6b, lb, and 82). Closingvalves 9, l and I l are arranged in the outlet pipes Bb, lb and 81). Asclearly shown in the drawing each annular screening member 4 has aninner face located in the screening chamber and an outer face whichfaces downwardly. The inclined annular screen members 4 are protectedfrom the pressure of the material by the supporting plate members whichmay have projecting edge portions 5a. The outer faces of the screenmembers 4 define with the vertical an angle which is at least as greatas the angle formed between the vertical and the resultant of thehorizontal and vertical components of the pressure in the treatedmaterial whereby any pressure due to the weight of the material on thescreen surfaces is prevented.

The washing process as effected with the above described washing tank issimilar to that on employing diffusers of the known type. However, if sodesired, at the end of the washing process when the boundary layerbetween the liquid to be displaced and the washing liquid has reachedthe uppermost annular screening chamber, it is advantageous to shut offthe outlets from the uppermost compartment thereby avoiding unnecessarydilution of the liquid to be displaced. The same measure can be repeatedwhen the boundary layer reaches the next lower screening chamber deviceand so on.

In the embodiment shown in Fig. 2 the screen members are arranged so asto form the side walls 25 of radially arranged screening chamber devices23. According to this embodiment each screening chamber device has adownwardly and laterally inclined supporting top plate 23. From theunderside of each supporting top plate extend screen means, namely twoscreen members 25 which, together with the surface of the tank bottomand with the top plate 23, form a screening chamber communicating withoutlets 25. Outlets il l communicate through an annular pipe 24a with anoutlet pipe which is controlled by a valve 26. It will be understoodthat each of the elements described above may also find a usefulapplication in other types of washing tanks for fibrous materialdiffering from the types described above.

The invention is not intended to be limited to the detail shown sincevarious modifications may be made without departing from the spirit ofthe present invention.

What is claimed. new and desired to be secured by Letters Patent is: I

1. An arrangement for washing a fibrous ma terial, comprising, incombination, a substantially vertically arranged elongated. tank havinga wall formed with an inlet for material to be washed at the upper endof said tank and an outlet for washed material at the lower end of saidtank; at least one screening chamber device including at least oneinclined supporting plate member secured to the inner surface of saidwall and projecting from the same downwardly into the interi r of saidtank, said inclined supporting plate member having the highest pointthereof located adjacent to said wall of said tank, said plate memberbeing adapted to support material to be washed, inclined screen meansextending between the underside of said supporting plate member and saidinner surface of said wall so as to form a screening chamber bounded bysaid supporting plate member, said inner surface of said wall, and saidscreen means, said screen means having at least one outer face outsidesaid chamber and at least one inner face inside said chamber, said outerface of said inclined screen member facing downwardly; and outlet meansfor a washing liquid located on said tank communicating with saidscreening chamber.

2. An arrangement for washing a fibrous material, comprising, incombination, a substantially vertically arranged elongated tank having awall formed with an inlet for material to be washed at the upper end ofsaid tank and an outlet for washed material at the lower end of saidtank; at least one inclined supporting plate member secured to the innersurface of said wall and projecting from the same downwardly into theinterior of said tank, said inclined supporting plate member having thehighest point thereof located adjacent to said wall of said tank, saidplate member being adapted to support material to be washed; at leastone inclined screen member extending between the underside of saidsupporting plate member and said inner surface of said wall so as toform a chamber bounded by said supporting plate member, said innersurface of said wall, and said screen member, said screen member havingan outer face outside said chamber and an inner face inside saidchamber, said outer face of said inclined screen member facingdownwardly; and outlet means for a washing liquid located on said tankcommunicating with the lowermost point of said chamber.

3. An arrangement for washing a fibrous material, comprising, incombination, a substantially vertically arranged elongated tank having awall formed with an inlet for material to be washed at the upper end ofsaid tank and an outlet for washed material at the lower end of saidtank; at least one inclined annular supporting plate member secured tothe inner surface of said wall and projecting from the same downwardlyinto the interior of said tank and having a free annular edge, saidinclined supporting plate member having the highest point thereoflocated adjacent to said wall of said tank, said plate member beingadapted to support material to be washed; at least one inclined annularscreen member extending between the underside of said supporting platemember spaced from said annular free edge of the same, and said innersurface of said wall so as to form a chamber bounded by said support ingplate member, said inner surface of said wall, and said screen member,said screen member having an outer face outside said chamber and aninner face inside said chamber, said outer face of said inclined screenmember facing downwardly; and outlet means for a washing liquid locatedon said tank communicating with said chamber.

4. An arrangement for washing a fibrous material, comprising, incombination, a substantially vertically arranged elongated tank having awall formed with an inlet for material to be washed at the upper end ofsaid tank and an outlet for washed material at the lower end of saidtank; a plurality of inclined annular supporting plate members securedto the inner surfaceof said wall and projecting from the same downwardlyinto the interior of said tank and having a free annular edge, saidinclined supporting plate members having the highest point thereoflocated adjacent to'said wall of said tank, said plate members beingadapted to support material to be washed; a plurality of inclinedannular screen members, each screen member extending between theunderside of one supporting plate member spaced from said annular freeedge of the same, and said inner surface of said wall so as to form achamber bounded by said supporting plate member, said inner surface ofsaid wall, and said screen member, each of said screen members having anouter face outside said chamber and an inner face inside said chamber,said outer faces of said inclined screen members facing downwardly; andoutlet means for a washing liquid located on said tank communicatingwith the lowermost points of said chambers.

5. An arrangement for washing a fibrous material, comprising, incombination, a substantially vertically arranged elongated cylindricaltank formed. with an inlet for material to be washed at the upper endthereof and having a bottom wall formed with an outlet for washedmaterial in the center thereof; a plurality of elongated screeningchamber devices located on said bottom wall of said tank extendingradially with respect to said outlet, each oi said screening chamberdevices including an inclined elongated supporting plate member securedto and projecting downwardly from the cylindrical inner surface of saidtank into the interior of said tank andv having the highest pointthereof located adjacent said cylindrical inner surface, said plate,;member being adapted to support material to be washed, and inclinedscreen means including two inclined screen members, each screen memberextending between the underside of said plate member and the innersurface of said bottom wall adjacent to a longitudinal edge of saidsupporting plate member, said supporting plate members, said screenmembers and the inner surface of said bottom wall defining an elongatedscreening chamber in each of said screening chamber devices, each ofsaid inclined screen members having an outer face located outside of thecorresponding chamber and an inner face located inside saidcorresponding chamber, said screen members being inclined with saidouter faces facing downwardly; and outlet means for a washing liquid insaid bottom wall of said tank communicating with the lowermost portionsof said elongated screening chambers.

6. Arrangement for washing material, comprising, in combination, a tankhaving an inlet for the material to be washed located in the upper partof said tank, and an outlet for washed material on the bottom of thesame; at least one inclined supporting plate member having an upper anda lower edge and being secured to the inner surface of said tankprojecting from the same inwardly and downwardly into the interior ofsaid tank, said supporting plate member being adapted to supportmaterial to be washed; at one screen member mounted in said tankextending downwardly from the underside of said supporting plate memberbetween the same and said inner surface of said tank so as to formtogether with said inner surface of said tank and. with said inclinedsupporting plate member a chamber bounded on one side by the inner faceof said screen member, said screen member having an upper edge locatedon said underside of said supporting plate member and a lower edgelocated on said inner surface of said tank, and an outer face extendingfrom said upper edge to said lower edge thereof and being inclinedrelative to a vertical passing through said upper edge thereof towardsaid upper edge of said supporting plate member so as to facedownwardly; and outlet means for a washing liquid mounted on said tankand communicating with said chamber.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 745397 Hood Dec. 1, 1903 1,776,761 Morterud Sept. 23, 19301,977,909 Goldberg Oct. 23, 1934 FOREIGN PATENTS Number Country Date63,250 Sweden Feb. 4, 1925 45, 427 Norway July 30, 1928 78,662 SwedenSept. 29, 1930 88,861 Sweden Jan. 21, 1937

